New study adds little clarity to our understanding of the benefits of compression socks.
Written by: Matt Fitzgerald
If you watched live television or online video coverage of the ING New York City Marathon on Sunday, you probably saw the 2009 champion, Meb Keflezighi, sporting a pair of white compression socks that rose to just below his knees. Although compression socks are primarily associated with recovery benefits, Meb obviously wasn’t wearing them during the most important race of the year to recover from the previous day’s shakeout jog. Nor is it likely that he wore them so that he’d have an easier time walking down stairs the next day. Instead, surely, he wore them for the same reason he did everything else that day: to enhance his performance in the race itself.
While Meb managed a sixth-place finish on a day that saw three men break the decade-old course New York City Marathon record, the 2004 Olympic Marathon silver medalist did set a personal best for the marathon distance–and at 36 years of age, no less. Does Meb have his compression socks to thank for his new PR?
The results of a new study suggest probably not. Conducted by a team of French researchers and published in the International Journal of Sports Medicine, the study involved 14 moderately trained athletes. These subjects were asked to perform a running test on two separate occasions. First they sat around for 15 minutes. Then they ran for half an hour at a moderate intensity. Next they recovered from this effort for 15 minutes and then ran to exhaustion at a pace equaling their previously determined maximum aerobic velocity. Finally, they recovered for 30 minutes.
On one occasion the subjects performed this test while wearing compression sleeves covering their lower legs. On the other occasion they just wore regular athletic socks. The researchers were interested in seeing not only whether the subjects would be able to run longer at their maximum aerobic velocity with the compression sleeves, but also whether they would exhibit higher levels of calf muscle tissue oxygenation, which the researchers measured before and after the performance test. Increasing oxygen supply to the working muscles is one proposed mechanism by which compression garments could enhance endurance performance.
However, in this study, the wearing of compression garments was not associated with improved performance. In fact, the subjects were able to run a few seconds longer, on average, without the compression sleeves than with them, although the difference was not statistically significant. This happened despite the fact that the compression sleeves did increase calf muscle tissue oxygenation before and after the performance test (hence presumably during the test, as well, although it was not possible to take this measurement during the test).
The increase in calf muscle tissue oxygenation was 6.4 percent (on average) before the performance test, and grew to 7.4 percent 20 minutes after the test and all the way to 10.7 percent 30 minutes after the performance test. Since oxygen supply to the muscles aids recovery, the authors of this study suggested that, although no performance benefit was seen, further research should be conducted to determine whether compression garments make a measurable difference in particular recovery parameters.
So it appears that Meb Keflezighi has only his training to credit—or perhaps his new Skechers GOrun racing flats—for his new marathon personal best time of 2:09:13. But if he kept his compression socks on after the race (or put on a clean pair), he just might be having an easier time walking down stairs today.
Matt Fitzgerald is the author of Iron War: Dave Scott, Mark Allen & The Greatest Race Ever Run (VeloPress 2011) and a Coach and Training Intelligence Specialist for PEAR Sports. Find out more at mattfizgerald.org.